Summary: The FitzGerald-Lorentz Solution to the Michelson-Morley Null Result

Specifically, what

means is that the time of light transit along both arms of the interferometer instrument is "equalized" by the doppler factor

because time

will be reduced by the same factor as the longitudinal arm

is also shortened by the same ratio

.

That is, the shorter is the longitudinal arm for light transit, therefore shortened will be the transversal transit time in the longitudinal component by time dilation!!

And in order, therefore, to maintain a universal constant speed of light in any light sphere in any direction by Einstein's special relativity physics proposition, longitudinal length contraction must be invoked!

More simply, length contraction is imputed in order to maintain a universal constant speed of light when determining time dilation in both Einstein's Special and General Relativity Physics equations!